1. Field of the Invention
The present invention relates generally to an electric motor assembly. More specifically, the present invention concerns an electric motor assembly that includes mounting structure configured to provide a mounting connection between the motor assembly and corresponding structure within a machine into which the motor assembly is to be mounted in a selected one of multiple motor dispositions, each corresponding with different motor axis positions.
2. Discussion of the Prior Art
Those of ordinary skill in the art will appreciate that electric motor assemblies are typically disposed within machines to drive a component or components during operation. There are many different types of machines where such an arrangement is incorporated, and design requirements will often dictate how and where the motor assembly is located within a given machine.
One common arrangement involves the motor assembly being used within a machine to power a driven element, such as through a drive belt. In such a situation, the disposition of the motor assembly within the machine can impact the tension in the belt. The design situation may arise whereby different motor assemblies are to be placed within similar machines, requiring a unique disposition for each exemplary motor assembly. For example, different models of an appliance, such as a washing machine, may selectively include different motor assemblies, with each motor assembly being designed to operate with a corresponding axis position and/or belt tension defined thereby.
Conventionally, the selection of one or another motor assemblies for use in a machine, where each motor assembly requires a different axis position, has required an individual mounting arrangement for each type of motor assembly. Often, a dedicated mounting part, such as a flange, is designed to cooperate with mounting structure within the machine to dispose the motor assembly in such a way that the axis is properly positioned for the desired construction. Traditionally, a unique component including the dedicated mounting part has been designed and manufactured for each individual motor assembly, such that the axis position is proper upon mounting the motor assembly within the machine. This has lead to an abundance of dedicated parts that must be manufactured, inventoried, tracked, and installed for a specific motor assembly design installation.
Even where multiple motor assemblies have been very similar in construction, and may even be designed to be optionally installed in similar machines, attempts to create a common endshield flange have proven difficult. Such common endshields have included multiple mounting holes within the same flange to optionally dispose a motor assembly in a variety of dispositions. These endshields have lead to confusion during assembly as to which set of mounting holes is to be used for a particular application, and have been regarded as aesthetically undesirable, as the unused mounting holes are left exposed and can create an unsightly condition to a customer.
While such conventional endshield mounting systems (dedicated parts or a common part with multiple hole sets) have been satisfactory in some respects, those of ordinary skill in the art will also appreciate that both options present drawbacks in at least cost and convenience. Designing and manufacturing a dedicated endshield with a unique mounting flange for each motor assembly application can require expensive die-casting, machining, stocking, and shipping of a multitude of specialized parts. This specialty process has lead to more part variations in casting databases and increases costs, as multiple dies and machining centers are typically required to provide the dedicated parts.
Similarly, common endshields with multiple mounting hole sets have proven difficult to reliably assemble properly, as a motor assembly that should be secured with one set of mounting holes may easily be improperly secured with an alternate set of mounting holes. Such errors in assembly can lead to significant problems in the situation where a parameter such as belt tension is defined by the disposition of the motor and position of the motor axis within a machine.